A waveform monitor apparatus (control device) for an injection molding machine described in Patent Literature 1 suggested by the applicant of this applicant has already been known as a conventional control device provided to an injection molding machine. This injection molding machine performs molding according to a specific molding system where an injection pressure (molding injection pressure) and a clamping force (molding clamping force) are obtained and set with which a parting opening to become a given clearance is formed between a movable mold and a fixed mold of a mold during injection-filling and which allow formation of a good molded article, a mold clamping device is clamped with the molding clamping force, and an injection device to apply the molding injection pressure as a limit pressure is driven, thereby injection-filling the mold with resin.
This waveform monitor apparatus (control device) allows change in the parting opening of the mold as an operation waveform relating to the mold clamping device to be monitored easily and effectively by visual recognition. Even in the injection molding machine that performs molding according to the specific molding system, this waveform monitor apparatus (control device) is intended to achieve sufficient monitoring during production, increase a molding quality, a yield and the like, and contribute to general versatility and expandability. More specifically, a waveform monitor apparatus for an injection molding machine for monitoring an operation waveform at least during molding is structured by being provided to the injection molding machine that performs molding according to a specific molding system where an injection pressure (molding injection pressure) and a clamping force (molding clamping force) are obtained and set with which a parting opening to become a given clearance is formed between a movable mold and a fixed mold of a mold during injection-filling and which allow formation of a good molded article, a mold clamping device is clamped with the molding clamping force, and an injection device to apply the molding injection pressure as a limit pressure is driven, thereby injection-filling the mold with resin. The waveform monitor apparatus includes a parting opening detecting means that detects data about change in the parting opening with time during molding, and an operation waveform display means that displays the change data detected by the parting opening detecting means at least in a period from when injection-filling of the mold with the resin is started to when cooling time of the mold is finished in a waveform display part on a screen on a display provided to a molding machine controller.